Briggs & Stratton — To Adjust Carburetor
Adjustments
From a Briggs & Stratton owner's manual — check it applies to your exact model before use.
Browse Briggs & Stratton generators & specs →
Before you start
- The manufacturer of the equipment specifies top speed at which the engine will be operated. DO NOT EXCEED this speed.
- DO NOT remove limiter caps. DO NOT force beyond limits.
Procedure
- Start engine and warm up approximately 5 minutes before adjusting.
- With engine running, place throttle control in SLOW. Rotate carburetor throttle lever against the idle speed screw and hold it.
- Turn idle speed screw to obtain 1200 rpm.
- While still holding carburetor throttle lever against idle speed screw, set cylinder #1 idle mixture valve midway between limits.
- Then set cylinder #2 idle mixture valve midway between limits.
- Readjust the idle speed to 1200 rpm if governed idle spring is red, or 900 rpm if governed idle spring is white.
- Release carburetor throttle lever. Move throttle control to FAST position. Engine should accelerate smoothly; if not, readjust idle mixture valves slightly counterclockwise.
Specs & values
- Idle speed 1200 rpm (red governed idle spring) or 900 rpm (white governed idle spring)
Source: Briggs & Stratton owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.